Field of the Invention
The present invention relates to a tongue pulling device including a pull plate, a pull line, and a retractor, which are implanted into the mandible and the tongue body of a human body, and more particularly to a tongue pulling device including a pull plate, a pull line, and a retractor implanted in the tongue base and/or the tongue dorsum for treating adult obstructive sleep apnea/hypopnea syndrome (OSAHS) and an implantation method.
Related Art
Adult OSAHS is a sleep breathing disorder with clinical features of snoring and apnea caused by upper airway collapse and obstruction during sleep. The major hazard of OSAHS is that frequent sleep apnea and hypopnea result in lowered oxygen saturation levels during sleep for a long term, causing a series of pathologic changes in the human body, thus becoming the cause of various systemic diseases (such as diabetes, hypertension, coronary heart disease, and cerebrovascular accident). According to statistics, currently the morbidity of OSAHS is up to 6%-7% among people, and is extremely high among the middle-aged, which seriously affects the health and quality of life. Therefore, it has been listed by the World Health Organization as one of the major diseases that affect the health and quality of life of people.
As for the pathogenesis of OSAHS, it is generally considered that the main cause is that, pharyngeal muscles for maintaining the upper airway open relax during sleep, resulting in soft tissue collapse and obstruction, and the plane of obstruction is usually located in the palatopharyngeal and glossopharyngeal portions. Many methods for treating OSAHS exist, which include two types, that is, non-surgical treatment and surgical treatment.
Methods of Non-Surgical Treatment Mainly Include:
1. Continuous Positive Airway Pressure (CPAP), in which a breathing machine capable of continuously generating a positive pressure is closely connected with the nose and face of a patient via a nasal mask, so as to prevent collapse and obstruction of the soft tissues of the airway during sleep. The method is currently preferred for treating OSAHS. Though the method has a good effect, it is difficult for approximately 50% of the patients to adapt to the machine, and they cannot endure the machine due to poor compliance, and cannot sleep when wearing the machine.
2. Oral appliance. A device is placed in an oral cavity to move forward the mandible or pull forward the tongue, so as to enlarge the pharyngeal cavity and release the airway obstruction during sleep. The method has many types and produces a certain effect, but most patients cannot adapt to it. The oral appliance leads to irritation and foreign body sensation, causing that the user cannot fall asleep, and may have temporo-mandibular joint injury with long term use.
3. Tongue pulling device. International Application PCT/US2005/00139, Jan. 3, 2005 has disclosed a method and a device for relieving upper airway obstructions. The device includes a mouthpiece that is adapted to form a sealed cavity within a patient′ mouth. The patient bites the device during sleep, and extends the tongue into the device, so as to form the sealed cavity. A negative pressure generator is connected with the device, which pulls the patient's tongue and/or soft tissues of the upper airway up and away from the posterior pharyngeal wall to open the airway, so as to prevent the occurrence of OSAHS.
Many patents similar to the tongue pulling device exist. All the patents use the teeth as a supporting point in the oral cavity, and various appliances are designed to change the tension state or position of the tongue or the soft palate during sleep, so as to achieve the objective of treating OSAHS and snoring. These appliances are placed in the oral cavity and are bitten and fixed before sleep, but since persons continuously change the posture and mouth shape during sleep, the appliances often cannot function effectively. In addition, it is uncomfortable and inconvenient for the patients to use the appliances.
Methods of Surgical Treatment Mainly Include:
1. Radiofrequency ablation, which is also referred to as low-temperature plasma radiofrequency ablation, and is a minimally invasive surgical method. An electrode is penetrated into the soft tissues which cause airway obstruction, such as the soft palate, tonsil, and tongue base, and is electrified to induce tissue coagulation, necrosis, fibrosis, and contraction by heating. The method has a certain therapeutic effect, is effective for a slight case, has a poor long-term efficacy, and is ineffective for serious patients. Since the method causes severe post-surgical responses such as tissue edema and pain and requires multiple surgical operations, it is not easily acceptable to the patients.
2. Palatopharyngoplasty. Since Fujita improved the Palatopharyngoplasty of Ikematus, a Japanese scholar, into uvulopalatopharyngoplasty (UPPP) and introduced it to the US in 1981, various improved surgical procedures based on UPPP, including Simmons method, Fairbanks method, Dickson method, Woodson method, Z-palatoplasty (ZPP), uvulopalatal flap (UPF) and H-uvulopalatopharyngoplasty (H-UPPP) have been successively reported in literatures, which made a great contribution to symptom alleviation and recovery of OSAHS patients. Countless patients benefit from the surgical treatment solution. However, in terms of long-term effect, since the mucous membrane and soft palate tissue structure are excessively removed, functional muscles are injured, resulting in complications of nasal regurgitation during swallowing, rhinolalia aperta, and nasopharyngeal stenosis and atresia. It is the leading edge and focus for the research and development of OSAHS treatment technologies nowadays to develop a method and corresponding surgical instruments which create a smaller wound or perform surgical treatment in a minimally invasive manner.
3. Soft palate implantation. International Application PCT/US2002/007966, Mar. 14, 2002, has disclosed a braided palatal implant for snoring treatment. In the invention, the braid is implanted into the soft palate to alter the center of gravity of the soft palate when swinging with the air flow and alter the aerodynamic characteristics of the soft palate, so as to increase the critical air flow speed at the soft palate and the pharynx, thereby preventing snoring from occurring. However, the method fails to prevent OSAHS from occurring, for OSAHS occurs when the soft palate collapses and obstructs the upper airway, so that the method and the adopted implanted instrument cannot be used to treat OSAHS. For serious snoring patients, the risk of OSAHS is increased because the weight at the swinging portion of the soft palate is increased.
4. Tongue reduction surgery. An electrosurgical knife or a laser is applied to remove tissues of the tongue body or tongue base portion, so as to achieve a volume reduction effect. However, the method creates a large wound, and easily hurt important nerves and blood vessels of the tongue, impairing the normal function of the tongue.
5. Tongue advancement surgery, including various surgical procedures such as advancement genioplasty and mandibular sagittal split osteotomy. However, the former has a poor long-term efficacy, and the latter creates a large wound.
6. Surgery using electrical stimulation of the tongue muscles. U.S. Pat. Nos. 7,660,632B2, 6,587,725B1 and 6,251,126B1 introduce a method that uses electrical stimulation of the hypoglossal nerve and the tongue muscles to cause contraction of the tongue muscles when a patient is asleep lying on his/her back, so as to keep the airway behind the tongue. The effectiveness and tolerance of the method needs to be clinically evaluated.
7. Tongue base pulling surgery. In June 1997, Ze'ev Sohn disclosed a method for treating OSAHS by using a surgical suture to pull the tongue dorsum portion and/or the tongue base portion in U.S. Pat. No. 5,988,171, which is characterized in that one end of the surgical suture is fixed using a bone screw, and then the surgical suture is passed across the tongue base portion, drawn, tied at the bone screw, and fixed, so as to pull the tongue base portion to enlarge the airway at the glossopharyngeal portion, thereby treating OSAHS.
The existing technical solution of tongue base pulling has the following three problems:
Firstly, the muscular layer of the tongue base portion belongs to soft tissues, the tongue muscles needs to move during speaking and swallowing every day, and different movements of the tongue muscles produce different forces. Since the surgical suture and the anchor are linear objects, they have a small contact area, and impose a cutting effect on the muscular layer of the tongue base portion under long-term alternate tensions, so that the fixing portion displaces, the tension is loosened, and finally the effect of tightening the tongue base portion is lost, failing to enlarge the airway at the glossopharyngeal portion.
Secondly, since the movement of the tongue is rather complex, the single-wire or double-wire tightening mode easily causes movement from the original implantation site. As a result, a wrong portion is tightened, and the tension is loosened, failing to enlarge the airway at the glossopharyngeal portion.
Thirdly, the tongue base pulling technology in the prior art does not allow adjustment after surgery, and the forward pulling distance of the tongue base portion and the tension can only be determined during surgical implantation. Since the contraction of scar tissues resulting from surgery varies greatly with different subjects, the forward pulling distance determined during surgery may not be that after recovery. However, if it is required to adjust the forward pulling distance of the tongue base portion, another surgery is needed, creating a new wound, and incurring additional medical expenses.
Based on the above, though generating a certain effect, the tongue base pulling method in the prior art for treating OSAHS and snoring still have many defects, and especially it is difficult to control the pulling tension. If the tension is too high, the patient will feel discomfort, and the swallowing and speech functions are affected. If the tension is too low, an effective pulling effect cannot be achieved, resulting in poor efficacy. Therefore, it is necessary to provide a novel technical solution for treating OSAHS, in which the new method should create a wound as small as possible, and the new instrument should be safe, effective, simple, and reliable.